Usage Of NASA's Near Real-time Solar And

Meteorological Data For Monitoring Building

Energy Systems Using RETScreen

International’s Performance Analysis Module

5/17/2012 1

Paul Stackhouse and Robert Charles

NASA Langley Research Center (LaRC)

Urban Ziegler and Gregory J. Leng

RETScreen International CanmetENERGY/NRCan

LaRC Team Members: William Chandler, David

Westberg, James Hoell and Taiping Zhang, SSAI

RETScreen Team Members: Nathalie Meloche,

Kevin Bourque, Farah Sheriff, Tommy Anderson

and Julien Poirier

NASA LaRC Research and Applied Science

5/17/2012 2

NASA Applied Earth Science:

POWER Project

POWER = Prediction of Worldwide (renewable) Energy Resource

Objective: Improve the Nation’s public and private capability for integrating environmental data from NASA research to support energy production and increased energy efficiency.

Goals: Through partnerships derive/validate/provide

parameters relevant to industry needs; link to decision support, transition when possible.

Applied Sciences Goal: The Applied Sciences

program extends NASA Earth Science research and

observations for practical use in environmentally-

related decision and policy making.

• Emphasizes partnerships in variety of application

theme areas Climate & Energy

Key Theme

NASA LaRC Research and Applied Science

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POWER

Web Site http://power.

larc.nasa.gov

Provides access to

both Long-term and

Near Real-Time

data sets from

NASA research

tailored to energy

and building

industry needs

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Decision Support: RETScreen

www.retscreen.net

• Clean Energy Project

Analysis Tool

• Aimed for both

feasibility and detailed

scenario analysis

• RETScreen 4 built on

Excel; RETScreen Plus

PC stand alone

• Partners since 2000

• Over 330,000 users in

36 different languages

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RETScreen Plus

Objective: Enable “users to monitor, analyze and report key energy performance data to facility operators, managers and senior decision-makers.”

Usage: 1. Determine & obtain building

energy and meteorological information for any location in world

2. Use multivariate analysis to determine system performance as a function of meteorological variability

3. Monitoring building energy performance for system changes, target higher efficiency and reporting verification

Average Insolation Incident On A

Horizontal Surface

SWV_

DWN

kWh m-2

day-1

CERES

FLASHFlux1

0.0

(0.1%)

0.69

(15.6%)

0.940

Average Atmospheric Pressure PS kPa GEOS 5.22 -- -- --

PS corrected to elevation PSC kPa GEOS 5.22 -0.72 2.41 0.998

Average Air Temperature At 2 m T2M Co GEOS 5.22 -0.01 2.62 0.953

Minimum Air Temperature At 2 m T2MN Co GEOS 5.22 0.91 3.52 0.920

Maximum Air Temperature At 2 m T2MX Co GEOS 5.22 -0.93 3.37 0.936

Relative Humidity At 2 m RH2M % GEOS 5.22 -0.01 11.3 0.618

Average Earth Skin Temperature TSKIN Co GEOS 5.22 -- -- --

Wind Speed At 10 m WS10M m/s GEOS 5.22 0.37 1.81 0.446

NASA’s Near Real-time Daily Averaged

Data Time Series Parameter Variables Units Source Bias RMS

R2

1CERES FLASHFlux – NASA satellite based; validation using NOAA SURFRAD

measurements from 2008 – 2010 in US. 2GEOS 5.2: Assimilation model results; atmospheric model optimized by

observations; validation using NCDC surface weather observations worldwide

5/17/2012 6 NASA LaRC Research and Applied Science

Monitoring and Targeting Case 1:

NASA LaRC Badge and Pass Office

Example

Kiosk display

output

5/17/2012 7 NASA LaRC Research and Applied Science

Step 3: Cumulative differences in output relative to system function shows noise but performance steady.

Step 1: LaRC based CERES FLASHFlux project surface solar flux (blue) vs. Solar Panel Electrical Output (green) gives excellent correlation.

RETScreen Plus Tool

Step 2: Regression relationship defines the system as a function of available solar energy

Total Energy = 59,000 kWhr, 18% greater than specified

Monitoring and Targeting Case 1:

NASA LaRC Badge and Pass Office

8

Monitoring and Targeting Case 2:

Apartment Building Cluster, Höganäs, Sweden

• Apartment

building complex

in Sweden

• Use RETScreen

Plus & NASA

temperature data

to assess energy

usage before and

after energy

efficiency upgrade

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Step 2: Evaluate cumulative difference over entire period – system change clearly shown since fit includes points before and after change

Monitoring and Targeting Case 2:

Apartment Building Cluster, Höganäs, Sweden

RETScreen Plus Tool

Step 1: Regress Heating Degree Day (16 C) from NASA GEOS 5.2 Reanalysis to Apartment Complex Energy usage for entire period

Pass 1: Identified system upgrade point

10

Step 2: Evaluate cumulative difference over entire period – system change clearly shown since fit includes points before and after change

Monitoring and Targeting Case 2:

Apartment Building Cluster, Höganäs, Sweden

RETScreen Plus Tool

Step 1: Regress Heating Degree Day (16 C) from NASA GEOS 5.2 Reanalysis to Apartment Complex Energy usage for period preceding change

Pass 2: Define system before change, assess impact

Energy Efficiency Upgrade

Savings 1st

Year: 224 MWhr

Savings

2nd Year:

337 MWhr

Total 2 Year Savings ~ $50,000 US

11

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Conclusions

• NASA near-real time data sets and RETScreen Plus tool together provide a new capability to assess building energy system performance at any location in the world.

– Meteorological data sets from atmospheric reanalysis

– Solar energy flux inferred from satellite analysis

• The RETScreen Plus tool using NASA data was able to:

– Improve understanding and assess performance of a NASA solar power system in VA, USA.

– Provide an estimate of energy savings (and thus cost) for an apartment building complex in Sweden

• These examples show the usefulness of RETScreen Plus coupled with satellite analysis and modeling to contribute to energy efficient increases worldwide